Vol. 64 | nr. 1 | Ianuarie - Martie 2016 Articolul 12

The Quality of the Prediction for the NVIS Propagation with ITS-HF Propagation
(Full text in English)

The article presents a study on the prediction quality of the ITS HF Propagation application suite: VOACAP (Voice of America Coverage Analysis Program), ICEPAC (Enhanced Profile Ionospheric Communications Circuit Analysis and Prediction Program) and REC533 (ITU Recommendation RS 533) for point to point connections of the NVIS (Near Vertical Incidence Skywave) type. The simulation results were compared to the measurements obtained on a NVIS direction carried out in Romania and with the measurement results obtained and published by Walden in [1] for a NVIS network established in the UK. Compared with the measurement data obtained in Romania, the results predicted by the three applications have achieved average values of the correlation factors. These low values regarding the quality of a predictive application are due to the short observation period of the ionospheric channel. In these circumstances, REC533 achieved the lowest mean value of the standard deviations compared to VOACAP and ICEPAC. Regarding the measurement results published by Walden, the three applications have achieved strong values. These results lead to high values of the coefficient of determination, ensuring a very good power of prediction. REC533 provided the most correlated values and the lowest average value of standard deviations. The results provided by ICEPAC and VOACAP are highly correlated for each month under review. Of the three applications analysed, the best predictions were obtained by REC533.
Keywords: NVIS, propagation prediction, HF measurements, VOACAP, ICEPAC, REC533